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Data Security 1 Exercises. Reading. 3. Reading 3. To transfer program control to the virus. The Misdirection, Reproduction, Trigger and Payload routines. It returns control to the program as originally written. Reading. 5. Reading 5.
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Data Security 1 Exercises
Reading 3
Reading 3 • To transfer program control to the virus. • The Misdirection, Reproduction, Trigger and Payload routines. • It returns control to the program as originally written.
Reading 5
Reading 5 • They reproduce inside a host which they damage or destroy. • It can copy itself into any program files. • They can stay dormant in the memory until triggered. • Displaying a message on the monitor screen or deleting files on the hard disk. • COM or EXE programs. • 1c 2b 3d 4a • A Trojan has a payload but no reproduction routine.
When a dismissed employee's name is deleted from the company’s payroll, a logic bomb is activated which causes the payroll records to be destroyed. • When a certain date occurs, a trigger routine is activated which makes keys beep when pressed and corrupts floppies. • When the hundred and twenty-ninth time, a trigger routine is activated which causes the screen to display, ‘Bloody! June 4, 1989’. • When the infected program is run, the boot sector is corrupted which causes the disk content to be overwritten and data to be lost.
5. When particular data occurs, payload is triggered which makes characters on a text mode screen slide down to bottom. 6. When an effected document is opened in the word processor, the virus macro is executed which attaches the virus code to the default template. When the user saves another document, the virus code attaches to the saved document. When the saved document is opened in the word processor, the virus destroys data , displays message or plays music.
A MIDI message encodes sound as 8-bit bytes of digital information. • The teacher is using a new program to encourage children to write stories. • The new version of SimCity has been enhanced in many ways. • A gateway enables dissimilar networks to communicate. • You can encrypt data to make it secure. • Ensure the machine is disconnected before you remove the case.
7.Designers can offer good ideas for brightening your website. 8. Electronic readers allow you to enlarge the print size. 9. Programmers write software which enables the computer to carry out particular tasks. 10. you can widen the picture on your monitor.
Problem Solving • F • H • C • A • E • G • B • D • J • i
Specialist Reading – Part A • A • C • Public-key cryptography. • Decrypt. • B • Information about the company operating the server and the server’s public key.
Specialist Reading – Part B • 1) a-iv b-iii c-i d-ii • 2)a-iii b-iv c-vi d-i e-ii f-v • 3)a-F b-T c-F d-F e-F f-F g-T h-T • 4) c,d,b,a